diff --git a/tetris/modes/marathon_a1.lua b/tetris/modes/marathon_a1.lua
index 515d056..2f93443 100644
--- a/tetris/modes/marathon_a1.lua
+++ b/tetris/modes/marathon_a1.lua
@@ -33,6 +33,7 @@ function MarathonA1Game:new()
 	
 	self.randomizer = History4RollsRandomizer()
 
+	self.additive_gravity = false
 	self.lock_drop = false
 	self.enable_hard_drop = false
 	self.enable_hold = false
diff --git a/tetris/modes/marathon_a2.lua b/tetris/modes/marathon_a2.lua
index 014fc77..2f63813 100644
--- a/tetris/modes/marathon_a2.lua
+++ b/tetris/modes/marathon_a2.lua
@@ -34,6 +34,7 @@ function MarathonA2Game:new()
 		"GM"
 	}
 
+	self.additive_gravity = false
 	self.lock_drop = false
 	self.lock_hard_drop = false
 	self.enable_hold = false
diff --git a/tetris/modes/marathon_a3.lua b/tetris/modes/marathon_a3.lua
index dffde93..bc7c374 100644
--- a/tetris/modes/marathon_a3.lua
+++ b/tetris/modes/marathon_a3.lua
@@ -39,6 +39,7 @@ self.SGnames = {
 		"GM"
 	}
 	
+	self.additive_gravity = false
 	self.lock_drop = true
 	self.lock_hard_drop = true
 	self.enable_hold = true